Project description:Fuchs endothelial corneal dystrophy (FECD) is a vision impairing pathology affecting the endothelial cells of the cornea. To better understand the disease, we developed a method to cultivate FECD cells isolated from surgical specimens. Using gene profiling, we compared the mRNA profiles of passage 2 FECD cells with passage 2 non-pathological corneal endothelial cells isolated from eye bank donor corneas.
Project description:Fuchs’ endothelial corneal dystrophy is major corneal disorder in the western world affecting the innermost part of the cornea, which leads to visual impairment. The morphological changes observed in Fuchs’ endothelial corneal dystrophy is well described, however, much less in known of the pathology at the molecular level. As the morphological changes observed in the cornea is profound in the extracellular matrix we sought to determine in protein profiles and changes herein in the Descement’s membrane and endothelium layer of Fuchs’ endothelial conrneal dystrophy patients when compared to healthy control tissue. Using the extracted ion chromatogram label-free MS based quantification method we quantified approximately the 50 most abundant proteins of the Descemet’s membrane and endothelial layer in in patient and control tissue. In addition, using the isobaric tag for relative and absolute quantification MS method resulted in a total of 22 regulated proteins of which the majority were extracellular proteins known to be involved in proper assembly and modulation of the basement membrane in other tissues. Many of the regulated proteins were furthermore among the most abundant proteins quantified. The two MS methods performed here suggest altered arrangement of the extracellular matrix in Fuchs’ endothelial corneal dystrophy and provide new candidate proteins that may be involved in molecular mechanism of this disease.
Project description:Transparency of the human cornea is necessary for vision. Fuchs Endothelial Corneal Dystrophy (FECD) is a bilateral, heritable degeneration of the corneal endothelium, and a leading indication for corneal transplantation in developed countries. While the early onset, and rarer, form of FECD has been linked to COL8A2 mutations, the more common, late onset form of FECD has genetic mutations linked to only a minority of cases. Epigenetic modifications that occur in FECD are unkonwn. Here, we report on and compare the DNA methyhlation landscape of normal human corneal endothelial (CE) tissue and CE from FECD patients using the Illumina Infinium HumanMethylation450 (HM450) DNA methylation array. We show that DNA methylation profiles are distinct between control and FECD samples. Differentially methylated probes (10,961) were identified in the FECD samples compared with the control samples, with the majority of probes being hypermethylated in the FECD samples. Genes containing differentially methylated sites were disproportionately annotated to ontological categories involving cytoskeletal organization, ion transport, hematopoetic cell differentiation, and cellular metabolism. Our results suggest that altered DNA methylation patterns may contribute to loss of corneal transparency in FECD through a global accumulation of sporadic DNA methylation changes in genes critical to basic CE biological processes Methylation of DNA is a key epigenetic mark that occurs in aging tissues. Altered DNA methlyation patterns have been observed in several late onset, and progressive ocular diseases including macular degeneration, glaucoma, and cataracts. While DNA methylation changes also occur in the common, late onset corneal dystrophy, FECD, has not been previously studied. Fuchs Endothelial Corneal Dystrophy (FECD) is a bilateral, heritable degeneration of the corneal endothelium, and a leading indicatioin for corneal transplantation in developed countries. Our study examined and compared the genome-scale DNA methylation profiels of corneal endothelial tissue from normal control and FECD patients using the Illumina Infinium HumanMethylation450 (HM450) DNA methylation array. We show that DNA methylation profiles are distinct between control and FECD samples. Differentially methylated probes (10,961) were identified in the FECD samples compared with the control samples, with the majority of probes being hypermethylated in the FECD samples. Genes containing differentially methylated sites were disproportionately annotated to ontological categories involving cytoskeletal organization, ion transport, hematopoetic cell differentiation, and cellular metabolism. Our findings suggest that alterations in DNA methylation may contribute to FECD pathogenesis by modifying the expression of genes with critical biological roles in the corneal endothelium. Our study has important clinical implications as FECD is a leading indication for corneal transplantationin the geriatric population. The effective medical treatment of FECD is a major unmet clinical challenge. Our findings suggest altered DNA methylation as a novel candidate therapeutic target in FECD
Project description:This dataset contains proteomic profiles of Descemet's membrane (DM) with corneal endothelial cells derived from patients with Fuchs endothelial corneal dystrophy (FECD) and non-FECD subjects by shotgun proteomics. FECD is the most common inherited corneal disease. Fibrillar focal excrescences, called guttae, and corneal edema due to corneal endothelial cell death result in progressive vision loss. Our dataset indicated that 32 distinctive molecules were expressed only in the FECD-DM but not in the DM of the control subject, possibly having important roles in the pathophysiology of FECD.
Project description:Fuchs’ endothelial corneal dystrophy (FECD) is a progressive vision impairing disease caused by thickening of Descemet’s membrane and gradual degeneration and loss of corneal endothelial cells. The aim of this study was to identify differentially expressed genes between FECD-affected and unaffected corneal endothelium to gain insight into the pathophysiological mechanisms underlying this disease. Microarray gene expression analysis was performed on total RNA from FECD-affected and unaffected corneal endothelium-Descemet’s membrane (CE-DM) specimens using the Illumina HumanHT-12 v3.0 expression array. RNA from pools of FECD-affected (n=3 per pool) and individual unaffected (n=3) specimens was used for comparison. Altered expression of a sub-set of differentially expressed genes was validated by quantitative reverse transcription-polymerase chain reaction (qRT-PCR) in independent specimens. Bioinformatics analysis was performed using InnateDB to reveal functional relationships among the differentially expressed genes and molecular pathways involved in the disease. A total of 16,513 genes were found expressed in the corneal endothelium of which 142 genes were differentially expressed between FECD-affected and unaffected endothelium (log2 fold-change ≥1.5, corrected p-value ≤0.05). Most of the genes were up-regulated (126) and a small proportion down-regulated (16) in affected corneal endothelium. Of the twelve genes prioritised for validation, differential expression of 10 genes, including those ranked 57th and 81st by significance validated by qRT-PCR (8 up-regulated and 2 downregulated, corrected p ≤0.05), one gene showed a trend for up-regulation in affected endothelium, consistent with the microarray analysis and another was up-regulated in an independent study indicating robustness of the differential expression dataset. Bioinformatic analysis revealed significant over-representation of differentially expressed genes in extracellular matrix reorganisation, cellular remodelling, immune response, and inflammation. Network analysis showed functional inter-relatedness of the majority of the dysregulated genes and revealed known direct functional relationships between 20 of the genes; many of these genes have roles in macrophage differentiation, phagocytosis and inflammation. This is the second report of microarray gene expression analysis in FECD. This study revealed a set of highly dysregulated genes in the corneal endothelium in FECD. More than a third of the dysregulated genes in the disease have been discovered for the first time and thus are novel. The dysregulated genes strongly suggest the presence of phagocytic cells, most likely immune cells, and inflammation in corneal endothelium in the disease. This study provides a molecular framework for delineating the mechanisms underlying these cellular processes in FECD.
Project description:RNA-Seq splicing data from the corneal endothelia of FECD patients and controls reveal hundreds of differential alternative splicing events. These include events previously characterized in the context of myotonic dystrophy type 1 and epithelial-to-mesenchymal transition, as well as splicing changes in genes related to proposed mechanisms of FECD pathogenesis